Condensation-curable silicone resins have been widely used as electronics materials such as potting materials or sealants for buildings. These resins react with moisture in the air and are cured by a condensation reaction to form rubber-like bodies, and exhibit adhesion to base materials in contact with the resins during curing. However, conventional condensation-curable silicone resins have a problem of poor adhesion to components of semiconductor materials. For example, when used for optical semiconductor devices, conventional condensation-curable silicone resins are poorly adhesive to PPA (polyphthalamide resin), which is a reflecting material, and the adhesion is further reduced due to heat from light-emitting devices or a temperature cycle, which is likely to cause separation of silicone resins from base materials.
In order to solve these problems of adhesion, blending of adhesion-imparting agents such as silane coupling agents is usually suggested. For example, Patent Literature documents 1 and 2 disclose methods of blending a silane coupling agent containing an amino group or a glycidyl group, and Patent Literature 3 discloses a method for improving adhesion to a base material by using a silane coupling agent containing an urea bond.
Patent Literature 4 discloses a method of primer treatment of a base material in order to improve adhesion.
However, blending of a silane coupling agent as disclosed in Patent Literature documents 1 to 3 does not sufficiently improve adhesion to a base material, and further has a drawback of poor durability, e.g., reduction in adhesion due to remarkable moisture absorption.
Furthermore, primer treatment as disclosed in Patent Literature 4 has a problem of increasing the number of steps, and is therefore not economical.